The invention relates to doors of the above kind widely used in e.g. commercial vehicles with closed cargo space or in stationary and transportable containers. More particularly, the invention relates to a door block for such a door.
The invention relates to a door block for a door which is hinged on a casing around an opening in a wall, whereby the door comprises a rotatable closing rod, a handle on the closing rod and a cam fitted on the closing rod for engaging a keeper on the casing when the door is closed and the closing rod rotated into closed position by means of the handle, and the door block comprises blocking means arranged to in the blocking position extend across the closing rod with parts which, at least on the side of the closing rod that is facing in the opposite direction of the handle, are near the outer side of the door, and locking means mounted on the blocking means and arranged to, in the blocking position of the door block, lock the blocking means to the closing rod.
Doors of the above kind are widely used in e.g. commercial vehicles with closed cargo space or in stationary and transportable containers. In order to facilitate un- and loading, these doors are normally mounted in one of the ends of the respective container.
During transport and storage the doors are kept closed by one or several closing rods which often are locked in the locking position for protection against theft by means of e.g. a padlock that locks the handle to lock fittings on the door.
Doors locked in this way are however broken open relatively easily and quickly by sawing the handle over or breaking it or the lock fittings.
A door block with the above-mentioned blocking means and locking means can however protect the door far more securely against being broken open. If the door block is locked to the closing rod by means of the locking means, the rotation of the closing rod is blocked in the opening direction by the blocking means which on the side facing oppositely of the handle will hit the outer side of the door. The cam of the rod can therefore not be disengaged from the corresponding keeper on the casing, the result of which is that the door can be kept locked securely and effectively by the door block.
Such a door block is known from U.S. Pat. No. 5,775,747. In this case, the door block has blocking means in form of two separate parts which by mounting on the door are pushed together around the closing rod and locked in this position by means of a separate bolt. The two blocking parts are curved on the side facing the closing rod. In assembled and locked condition, the door block can therefore not be pulled free of the closing rod. The blocking part facing in the opposite direction of the handle hits the outer side of the door at attempts to rotate the handle in the opening direction. Thereby the door is effectively secured against being broken open.
This known door block is however relatively difficult to handle as it consists of three separate parts which only form the desired door block at assembly around the closing rod. Correspondingly, the three parts have to be separated from each other on site before they can be disengaged from the closing rod so that this rod can be rotated and the door opened.
The two blocking parts are assembled by means of a coupling wall which is made on one of the parts and inserted in the second part at assembly around the closing rod. However, there is only room for the coupling wall to have a limited thickness, and it can therefore not for certain absorb the relatively great moment that will affect it when an unauthorized person pulls hard on the handle in an attempt to open the door. In this case there is a risk of the coupling wall being bent so that the closing rod can be rotated after all. The known door block is therefore not able to for certain provide the required maximum security against burglary.
A corresponding door block is known from U.S. Pat. No. 5,791,702 that also consists of two separate blocking parts which have to be assembled on site in order to form the door block. The two parts are after assembly locked together with a separate bolt. One of the blocking parts is in this case shaped as a short, box-shaped length of pipe which at mounting is pushed in over the handle. The second blocking part is shaped as a double branched bracket, one branch of which is pushed into and locked in the box-shaped length of pipe at mounting. This door block is somewhat more difficult to handle than the door block known from U.S. Pat. No. 5,775,747.
The object of the invention is to provide a door block of the kind mentioned in the opening paragraph that is easy and convenient to use, that has a simple and inexpensive design, that can be used without having to use tools and without having to manipulate the structure of the respective door at all, that offers the greatest possible resistance against breaking open, and that clearly reveals if a burglary has taken place.
The novel and unique features according to the invention, whereby this is achieved, is the fact that the blocking means consist of a, seen in cross section, mainly U-shaped covering in form of a body having projecting flaps extending to the proximity of the outer side of the door in the locking position of the door block and together with the body during this encompassing the part of the handle that adjoins the closing rod, that in the flaps of the covering are made flushing cuts for in the blocking position receiving the closing rod, and that the locking means comprise a catch hook pivotally mounted in the covering and having a projection for in the blocking position locking the closing rod in the cuts, and a lock for locking the catch hook in its locking position.
As the door block according to the invention consists of only one single part, it can be mounted on and demounted of a closed door easily and quickly and without use of tools. The U-shaped covering of the door block can without difficulty be dimensioned to be able to absorb the moment from a hard pull on the handle. The door block therefore provides maximum security against burglary.
The application of the door block does not require any manipulation of the door, and a mounted door block cannot be removed from the locking position on the door without conspicuous damages which immediately would reveal the burglary.
When the covering furthermore is made of a strong material such as hardened or case-hardened steel, and has a relatively great material thickness, the door will be very difficult to break open, and a burglary will take relatively long time even if heavy tools are used for the purpose.
In a preferred embodiment the catch hook can in an angular distance from the first projection have a second projection which is arranged in such a way that the closing rod during insertion in the cuts of the flaps turns the catch hook into locking position.
Thereby the process of fixing the door block on the door is facilitated considerably, as the door block will put itself in the correct locking position by merely being pushed in over the respective closing rod.
The door block can furthermore be fixed securely and correctly on the door with merely one single motion of the hand when the catch hook only can pivot between a first angular position in which the first projection is beyond and the second is within the constraint of the cuts, and a second angular position in which the first projection is within and the second beyond this constraint.
In the first angular position the door block can simply be pushed in over the closing rod. In the second angular position the catch hook has locked itself on the closing rod so that the door block cannot be removed without being destroyed.
By letting the two projections of the catch hook pass into each other via a cylinder face section having the same or just slightly larger radius than the radius of the closing rod, the closing rod is able to successively turn the catch hook smoothly and slidingly from its first to its second angular position and vice versa when the door block is mounted on and demounted of the door, respectively. In fixed position the door block is furthermore firmly fixed almost without looseness on the closing rod.
When the cuts are extending obliquely outward in the flaps of the covering, the door block will be especially firmly fixed on the closing rod in the locking position. This advantage is obtained because a part of the flaps of the door block then will be extending behind the closing rod and thereby together with the locking projection of the catch hook contribute essentially to the strength of the door block against being pulled or broken off of the closing rod. An unauthorized person will therefore not be able to open the door without breaking the door block with heavy tools.
In a simple and effective embodiment the catch hook can have a first part provided with the two projections and a second part extending mainly perpendicularly from the first and arranged to lock the catch hook in its locking position in cooperation with the lock.
As lock there can be used a conventional padlock or a C-shaped lock which is fastened in the covering and locks with a bolt acting as stop to the second part of the catch hook when the catch hook is in the locking position.
In a second embodiment a cylinder lock can be used which is mounted in a housing with an axis extending crosswise to the flaps of the covering, in the housing is constructed partly an axial opening for a bolt, partly a transverse cut connecting the axial opening to the interior of the covering.
The catch hook can then be arranged in such a way that its second part is extending into the axial opening via the transverse opening when the catch hook is in the first angular position and is out of the axial opening when the catch hook is in the second angular position.
When the swivelling axis of the catch hook, the first projection and the end face of the second part are situated in each their peak of a triangle and a bolt is placed in the axial opening of the lock housing, the catch hook is forced to be in the second angular position, i.e. in the locking position, as the second part of the bolt is now prevented from swinging into the axial opening and thereby allowing the disengagement of the locking engagement of the catch hook.